timing was off - need to cancel context before returning early

scheduler.go

@@ -7,6 +7,7 @@ import (
 	"runtime"
 	"slices"
 	"strings"
+	"sync/atomic"
 	"time"
 
 	"github.com/google/uuid"
@@ -72,7 +73,7 @@ type scheduler struct {
 	// the location used by the scheduler for scheduling when relevant
 	location *time.Location
 	// whether the scheduler has been started or not
-	started bool
+	started atomic.Bool
 	// globally applied JobOption's set on all jobs added to the scheduler
 	// note: individually set JobOption's take precedence.
 	globalJobOptions []JobOption
@@ -233,13 +234,8 @@ func NewScheduler(options ...SchedulerOption) (Scheduler, error) {
 
 func (s *scheduler) stopScheduler() {
 	s.logger.Debug("gocron: stopping scheduler")
-	if !s.started {
-		s.logger.Debug("gocron: scheduler already stopped")
-		s.stopErrCh <- nil
-		return
-	}
 
-	if s.started {
+	if s.started.Load() {
 		s.exec.stopCh <- struct{}{}
 	}
 
@@ -250,7 +246,7 @@ func (s *scheduler) stopScheduler() {
 		<-j.ctx.Done()
 	}
 	var err error
-	if s.started {
+	if s.started.Load() {
 		t := time.NewTimer(s.exec.stopTimeout + 1*time.Second)
 		select {
 		case err = <-s.exec.done:
@@ -275,7 +271,7 @@ func (s *scheduler) stopScheduler() {
 	}
 
 	s.stopErrCh <- err
-	s.started = false
+	s.started.Store(false)
 	s.logger.Debug("gocron: scheduler stopped")
 }
 
@@ -480,7 +476,7 @@ func (s *scheduler) selectJobOutRequest(out *jobOutRequest) {
 
 func (s *scheduler) selectNewJob(in newJobIn) {
 	j := in.job
-	if s.started {
+	if s.started.Load() {
 		next := j.startTime
 		if j.startImmediately {
 			next = s.now()
@@ -531,7 +527,7 @@ func (s *scheduler) selectStart() {
 	s.logger.Debug("gocron: scheduler starting")
 	go s.exec.start()
 
-	s.started = true
+	s.started.Store(true)
 	for id, j := range s.jobs {
 		next := j.startTime
 		if j.startImmediately {
@@ -826,15 +822,16 @@ func (s *scheduler) StopJobs() error {
 }
 
 func (s *scheduler) Shutdown() error {
-	if !s.started {
+	s.logger.Debug("scheduler shutting down")
+
+	s.shutdownCancel()
+	if !s.started.Load() {
 		return nil
 	}
-	s.shutdownCancel()
 
 	t := time.NewTimer(s.exec.stopTimeout + 2*time.Second)
 	select {
 	case err := <-s.stopErrCh:
-
 		t.Stop()
 		return err
 	case <-t.C:

scheduler_test.go

@@ -568,10 +568,9 @@ func TestScheduler_Shutdown(t *testing.T) {
 		assert.ErrorIs(t, err, ErrJobNotFound)
 	})
 
-	t.Run("calling shutdown multiple times including before start is a no-op", func(t *testing.T) {
+	t.Run("calling shutdown multiple times is a no-op", func(t *testing.T) {
 		s := newTestScheduler(t)
 
-		assert.NoError(t, s.Shutdown())
 		s.Start()
 
 		assert.NoError(t, s.Shutdown())